The goal of this study is to measure and document the short- and long-term effects of prenatal tethering and catheterization, and to provide control data for fetal catheterization studies. In the past year we completed cage modifications for tethering and for urine/feces collection, and selected, purchased, constructed, and installed a new physiological monitoring system that incorporates an integrated microcontroller for system error monitoring and calibration. We have screened and selected the first two subjects, one control and one catheterized, and the first catheterization surgery has been completed successfully. We are currently involved in intense data collection, including fecal sampling for steroid analysis, urine sampling for cortisol analysis, blood sampling of dam and fetus for nutrition, immunology, and steroid analysis, various behavior sampling protocols, Doppler ultrasounds for fetal growth and blood flow, vaginal swabs for vaginal flora/fauna analysis, and monitoring of dam and fetal heart rate and blood pressure.